Steam-boiler



(No Model.) I

H. N. EARTH, STEAM BOILER.

No. 521,844. Patented June 26, 1894.

I WIZWE'SSES [ME/V102? UMTE D STATES ATENT Fries.

HENRY N. EARTH, OF CHICAGO, ILLINOIS.

STEAM-BOILER.

.SFECIFICATION forming partof Letters Patent No. 521,844, dated June 26, 1 894.

Application filed October 27, 1893.- Serial No. 489,280. (No model.)

To alZ'whom it may concern:

Be it known that I, HENRY N. BARTH, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Steam-Boilers, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to steam boilers.

The object of the invention is to improve the construction of that class of steam boilers in which the fire-box is largely inclosed in the Water chamber, and in which fire-tubes or flues and water tubes are employed.

Figure 1 is a cross section of the'improved boiler, about on the line of the center of the steam done Fig. 2 is a central longitudinal section of the boiler, parts being broken away to show details which do not appear in the vertical central plane.

The numeral 1 indicates the outside shell of the boiler, which is preferably cylindrical inits general form, and may be of anyusual material and of proportions to secure satisfactory results under ordinary conditions.

The numeral 2 indicates an inner shell, which is nearly cylindrical, but preferably flattened at the top,and is held within the outer shell by stay' bolts 3, and forms near the rear end of the boiler the smoke and com- -bustion chamber 4., which chamber is inclosed by the end wall of shell 2 and the diaphragm 5. The shell 2 is not necessarily involved in some parts of this improvement." The steam dome 6 is riveted or otherwise secured to the shell 1,'and has a central open edge of the crown sheet.

ing 7, and side openings ,8, 8, into the shell 1,.

the latter serving as drip openings should any water enter the dome. Inside the outer shell, (and partly within the shell 2 should such be employed,) I place the firebox shell, which is composed of the arched piece 10 extending over the water chamber A, and the crown sheet 11, extending over the fire box, said arch and crown being connected at the The arch is continued down at the sides of the fire box, as at 12, 12, and the edges of the bottom tro'ugh 13 are connected to the lower edges of this extension of the arch plate, by rivets or otherwise. The bottom trough 13 has a concave central portion and its sides are prefertheir lower axes about horizontal.

steam boiler construction.

ably inclined planes as shown at B, B. The crown sheet 11 has a convex central portion, and inclined sides, preferably about parallel with the inclined sides of the bottom trough, and indicated at (J, G.

The water chamber A, between the crown sheet 11 and the arch 12, I have called the concentrator. The form of the concentrator approximates that of a segmentof a cylinder. The main shell and the concentrator have The concentrator or chamber has outlets, as 15, at

the top and sides above rivet seam. A series of water tubes 16 extend through'the inclined plates B and the inclined plates 0, and about parallel to the plates 12. These water tubes are preferably screwed into holes' 1n one of the plates B and expanded into holes of the other plate 0, or they may be otherwise secured to the plates in usual manner.

The tubes 16 thus form inclined passages through the fire box, near the sides thereof, and insure circulation of the water from the lower part of the shell through the concentrator, as long as the water line is above the top of the concentrator openings, by reason of the tendency of heated water in these small tubes to rise, in manner well known in is placed above the trough 13, and preferably The fire grate 20 an arch wall 21 at rear of the fire grate an-" swers as a support for the rear end of the grate, and the trough 13sorves as an ash pit.

A' corresponding arch or plate may be at the front of the grate bars, and easy access is had to the ash pit through openings in these arch walls. The front end of the fire box may be closed by any'usual form of door, as 26, and

the front of the boiler may be a water front or not, theusual conditions of the art being observed. The ash pit door 27 affords access to said pit. V be almost in contact with tubes 16, and the heated products of combustion from said fire will envelop said tubes, and will impinge against'said tubes and the crown sheet, and

Fire built on the grate will pass to chamber 4:, The tubes next the fire maybe protected bysleeves 16 so as not to be easily injured by coal on the grate, or by the direct contact of the fire. The concentrator and firebox are supported from the outer shell, and also from the inner shell,

IOO

when such is used, by suitable braces, or stays, some of which are indicated at 28. The location of these stays or braces is a matter of mechanical judgment.

Between the side walls 12 of the fire box, and the boiler shell, there is a considerable water space. This space is broken up by the return fiues or fire tubes 80, which extend from the chamber at forward through the water space to the saddle or uptake 33, the ends of these lines being expanded or otherwise secured in the shell plates and in the partitions of the boiler in manner well known in the art. The central part of the boiler thus becomes a water tube boiler, and the part outside the fire box a fire tube boiler, and all large bodies of water at a distance from the heating surfaces are avoided. The ends of these fire tubes are accessible through doors 34 in the chimney, hood, saddle, or uptake. The boiler is supported on any suitable setting, one form of support being indicated by the saddles E, E, supported on legs F, F. Suitable man-holes and covers as G, G, are provided, and braces H, H, are applied where needed, and in any usual manner. The sight hole K extends through an opening between the outeruand inner shells of the boiler, and is closed in any convenientway. Hand holes for cleaning the boiler are also provided (shown at M).

The main features of the invention in my boiler are embodied in the fire chamber with nearly vertical water tubes passing through the same, and the fire tubes forming return flues from the combustion chamber, but there are minor features of novelty in the device which I will endeavor to point out in the claims.

The boiler is specially intended for use as a marine boiler, but may be otherwise used, and some of the novel features are adapted for use with boilers of other and common construction. The crown sheet inclines toward the nearest tubes 16, so that sediment will not accumulate on the crown sheet but pass down the tubes. The man hole to the main shell gives immediate access to the concentrator, for construction, repairs, or cleaning. The steam dome is large so that a considerable body of water may be carried in the boiler and still leave room for dry steam, yet as shown no very considerable body of water is found far from aheating surface.

What I claim is 1. A horizontal generally cylindrical steam boiler having within the outer shell the chamber or concentrator approximating the segment of a cylinder extending horizontally within the outer shell and having a crown sheet over the fire chamber, and water tubes leading in a nearly vertical direction from the water space below the fire box, through the fire chamber, and into the concentrator, substantially as described.

2. In a steam boiler, the outer shell, the inner water chamber or concentrator, the fire box sides formed by the extension of the plates of said concentrator, the bottom trough and the watertubes leading from said trough through the fire box and into the concentrator, substantially as described.

3. In a steam boiler, the generally cylindrical horizontal shell, the concentrator inclosed therein, the fire box inclosed in the shell and having side walls and outer tubes extending in nearly vertical direction through said box to the concentrator above the same, and having fire tubes extending in horizontal direction at the sides of said fire box, substantially as described.

4. In a steam boiler, the outer shell, theinner fire box composed of inclined sides and a bottom trough and a grating, the concentrator above said fire box, the water tubes extending through said fire box, and the fire tubes extending from the inclosed chamber at the rear of the boiler alongside the fire chamber to the front of the boiler, all combined and relatively arranged substantially as described.

5. The concentrator inclosed in the boiler shell and having nearly vertical water tubes connecting therewith, and having a convex crown sheet with its sides inclined downward toward the ends of the adjacent water tubes, whereby sediment may pass to the tubes, all substantially as described.

6. The horizontal segmental concentrator inclosed in the main horizontal generally cylindrical shell and having nearly vertical water tubes entering the lower part thereof, and having openings at the upper part through which circulation is had, in combination with Y the fire box shell and accessories,substantially as described.

In testimony whereof I affix my signature in presence of two witnesses.

HENRY N. BARTII. Witnesses:

L. F. ALEXANDER, B. TnRAISOR. 

